Kim Sengupta: There are clear reasons why many believe the Lockerbie trial was a miscarriage of justice

Abdelbaset al-Megrahi, his face skeletal, could barely move. He was attached to a drip, his face covered by an oxygen mask, drifting in and out of consciousness. The medicine needed for his treatment had been plundered by looters; the doctors had fled.

That was how I found the man convicted of the Lockerbie bombing in Tripoli last Autumn, the reminder of the controversy surrounding an atrocity 24 years ago. His brother Abdelnasser asked "Why do they want so much to drag him back to suffer in prison? You are looking at a man who is very close to dying."

The vengeful pursuit of Megrahi, the feeling that he has somehow escaped justice by not actually dying in a cell, is the result of a genuine belief by some that he was guilty, allied to anger that his release was part of the many dodgy deals between the British government and Muammar Gaddafi's regime. Yet there are cogent reasons why so many others, including members of bereaved families such as Dr Jim Swire who lost his daughter Flora in the bombing, have been convinced that Megrahi's conviction was a miscarriage of justice.

Soon after the destruction of Pan Am flight 103 American and British officials were busy laying the blame on the Iran Syria axis. However, after Iran and Syria joined the US-led coalition against Saddam Hussein in the first Gulf War the same officials switched the blame to Libya, at the time very much a pariah state.

The trial of Megrahi and his fellow Libyan defendant Lamin Khalifa Fhimah at a specially constituted Scotttish court at Camp Zeist in the Netherlands came under criticism from international jurists. The two men were effectively charged with joint enterprise, yet only Megrahi was found guilty. The prosecution evidence was circumstantial; details of the bomb timer on the plane contradictory and the testimony of a key witness, a Maltese shopkeeper, shaky under cross-examination.

The evidence of a supposedly prime "CIA intelligence asset", codenamed "Puzzle Piece" who turned up in a Shirley Bassey wig, was widely viewed as risible. It emerged later that important evidence had not been passed on to the defence lawyers.

Professor Hans Kochler, a UN appointed legal observer, described the proceedings and a subsequent failed appeal by Megrahi as "inconsistent, arbitrary and a spectacular miscarriage of justice".

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